but last week investigators earned to that home where jackson used to live. cadaver dog a reacted to an area of the garage. that area was he can can straighted and bones were found. medical examiner says a preliminary assessment suggest that is the bones were from an animal. further tests are being conducted and the results are expected in a few weeks. jenna. jenna: we'll continue to watch those developments. patti ann, thank you. >> thank you. jon: a new study offers a startling prediction on the mental health of america's aging population. it suggests the number of alzheimer's cases could triple in the next 40 years. researchers tie the expected spike to aging baby boomers and hope the projections will compel them to take early steps for prevention. dr. leigh vinocur, adjunct, assistant professor i should say at lsu health sciences center in shreveport, louisiana. doctor vinocur how do we take steps to prevent alzheimer's if we don't know what causes it? >> that is a very good question, jon. it just highlights the need for more research and how we really, i